【摘要】 进化分析表明,与线粒体亲缘关系最近的原核生物是立克次体(Rickettsia prowazekii).搜索酿酒酵母(Saccharomyces cerevisia)线粒体蛋白转运系统的35个亚基在立克次体中的同源蛋白质,仅发现了5个同源蛋白,且它们只属于转运系统在线粒体外膜和基质上的模块,没有发现转运系统在膜间隙和内膜模块的同源蛋白.对大肠杆菌(Escherichiacoli K-12 MG1655)的分析也有类似的结果.因此线粒体蛋白转运系统应该不是直接起源于内共生的原核生物.更多还原

【Abstract】 Phylogenetic analyses identified that Rickettsia prowazekii is the closest relatives of modern mitochondria.The homology analysis results from the 35 subunits of mitochondrial protein import mechanism of Saccharomyces cerevisiae,with thoce of Rickettsia prowazekii,suggest that only 5 subunits of the machinery have orthologous sequences from Rickettsia prowazekii.These 5 subunits are located in the outer membrane and the matrix of mitochondria,while no subunit located in the inner membrane and intermembrane space.Analysis of the Escherichia coli K-12 MG1655 have similar results. Therefore,the mitochondrial protein import machinery should not be prokaryotic origin.更多还原